JP2002317880A - Motor-operated flow control valve - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the accuracy of flow control by making the starting point of a valve element to be turned correspond to a starting point of the exciting pattern of a stepping motor. SOLUTION: This motor-operated flow control valve comprises an upstream restricting valve part 41 consisting of an upper valve element 35 and an upper valve seat 32 and a downstream restricting valve part 42 consisting of a lower valve element 36 and a lower valve seat 33, the opening of one of two restricting valve portions being controlled with less-than-one turn of the valve element. Magnetic pole teeth 38a of a fixed coil 38, the upper valve seat 32 or the lower valve seat 33 and a stopper 40 are so assembled as to be located at mutual predetermined positions to form a fixed-side check part, and magnetic patterns of N and S poles of a rotor 34 and the upper valve element 35 or the lower valve element 36 are so assembled as to be located at mutual predetermined positions to form a moving-side check part. When the fixed-side check part and the moving-side check part are in mutual contact to produce mechanical check, the exciting pattern of the stepping motor is used as a starting point.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a stepping motor driving means for reversibly operating an upper valve body and a lower valve body which rotate integrally with a rotor for less than one rotation, and for rotating the valve body for less than one rotation. The present invention relates to an electric flow control valve that controls an opening degree of one of two throttle valve portions by turning, and in particular, precisely and precisely keeps a rotation starting point position of the upper valve body and the lower valve body for less than one rotation. Thus, the present invention relates to an electric flow control valve which ensures the accuracy of the actual valve opening with respect to the number of pulses applied to the coil.

[0002]

2. Description of the Related Art Conventionally, various types of motorized flow control valves which are controlled by a microcomputer by combining a stepping motor and a valve integrated with a valve shaft have been devised. FIG.
Is the structure of a conventional control valve filed by the applicant of the present invention in Japanese Patent Application No. 2000-297869, and the structure thereof will be described below. The conventional electric flow control valve has a cylindrical case 31.
The upper valve seat 32 and the lower valve seat 33 airtightly fixed to both ends of the cylindrical case 31 and the cylindrical rotor 3
4 and an upper valve body 35 and a lower valve body 36 which rotate by engaging with the rotor, a shaft 37 and a fixed coil 38.

[0003] The cylindrical case 31 has a cylindrical shape with both end faces made of non-magnetic metal.

[0004] The upper valve seat 32 and the lower valve seat 33 are disk-shaped, and have shaft holes 32a, 3a at the center thereof.
3a is provided, and valve ports 32b and 33b are respectively provided at positions slightly away from the center. Also,
In order to stabilize the rotation of the valve body, the valve port 3 is located on the sliding surface of the upper valve seat 32 and the lower valve seat 33 and at a position opposite to the valve ports 32b and 33b around the shaft 37.
Disc-shaped contact surfaces 32c protruding from the valve seat surface at a plurality of locations including the periphery of the valve seats 2b and 33b are provided integrally with the respective valve seats. In addition, communication holes 35g and 36g are provided in the wall surfaces of the upper valve body 35 and the lower valve body 36, respectively. The inflow / outflow pipes 39a and 39b are hermetically fixed to the valve ports 32b and 33b of the valve seat.

An upper valve seat 32 and a lower valve seat 33 are air-tightly fixed to both ends of the cylindrical case 31, and a stopper 40 is fixed to the lower valve seat 33. .

Further, a piston ring 44 is provided on the outer peripheral surface of the upper valve body 35 and the lower valve body 36, and the piston ring 44 allows the inner peripheral surface of the cylindrical case 31 to be connected to the upper valve body 35. The refrigerant can be prevented from flowing into the gap between the lower valve body 36 and the outer peripheral surface of the rotor 34.

[0007] The cylindrical rotor 34 is provided with cutouts (without reference numerals) at its upper end and lower end, and the cutouts are formed by projecting an upper valve body 35 and a lower valve body 36 described later. It engages with the portions 35c and 36c, and positions the rotor 34, the upper valve body 35 and the lower valve body 36 in the rotation direction.

The upper valve body 35 and the lower valve body 36 have a cylindrical shape, and are provided with shaft holes 35a and 36a at the center thereof. A stepped shape so as to fit with the inner diameter of the rotor, and a protrusion 35c corresponding to the notch of the rotor;
36c is provided.

The upper valve body 35 and the lower valve body 36 are located at positions corresponding to the valve ports 32b, 33b of the upper and lower valve seats.
Grooves 35d and 36d whose cross-sectional areas gradually change with the rotation direction are provided, and communication holes 35b and 36b are provided at positions where the cross-sectional areas of the grooves are maximum, and as shown in FIG. Pipe 39b → valve opening 33b of lower valve seat 33 →
The communication hole 36b of the lower valve body 36 → the inside of the rotor 34 → the communication hole 35b of the upper valve body 35 → the valve port 32b of the upper valve seat 32 →
It flows to the inflow / outflow pipe 39a. When the flow direction of the refrigerant is reversed by switching between the cooling and the heating of the heat pump type refrigeration cycle, it goes without saying that the above-described flow path of the refrigerant is reversed.

The lower valve element 36 is provided with a locking piece 36f corresponding to the above-described stopper 40 of the lower valve seat, and when the locking piece 36f contacts the stopper 40, the rotor 36 is rotated. The rotation end position when the upper valve body 34 and the upper and lower valve bodies rotate is regulated.

Further, in the conventional electric flow control valve, the upper valve body 35 and the upper valve seat 32 constitute the upstream throttle valve portion 41 and the lower valve body 36 in the above-described electric flow control valve. The lower throttle seat 33 constitutes the throttle valve portion 42 on the downstream side.

The shaft 37 is connected to the rotor 34 and the upper valve body 35.
And both ends of the shaft 37 are axially supported by the shaft holes 32a, 33a of the upper valve seat 32 and the lower valve seat 33, respectively. It penetrates the shaft holes 35a and 36a.

The refrigerant flowing from the communication port 36b of the lower valve body 36 flows into the valve port 33b of the lower valve seat 33 through a groove 36d whose sectional area gradually changes as the valve body rotates. The flow rate of the refrigerant is reduced by the size of the cross-sectional area of the groove 36d at a position where the refrigerant is in contact with the valve port 33b of the lower valve seat 33. That is, the refrigerant passage amount can be adjusted by the rotation position of the lower valve body 36 that is rotated by less than one rotation of the rotor 34, and the capacity control of the refrigeration cycle can be performed.

[0014]

However, in the electric flow control valve shown in FIG. 5, when the rotation of less than one rotation is rotated in the closing direction or the opening direction and mechanically stopped by the stopper 40, However, the excitation pattern of the stepping motor is not set to be the excitation pattern used as the origin. For this reason, at the start of use as the electric flow control valve, the initialization operation is performed by giving a pulse signal (the number of pulses greater than the number of pulses for switching from the fully open state to the fully closed state) from the microcomputer, and mechanical operation by the stopper 40 is performed. Even when the rotation is stopped at the origin position of the rotation by the stop, when the excitation pattern used as the origin, which is the final excitation pattern of the initialization operation, becomes the fixed coil 38 having magnetism in the excitation pattern used for the origin. A magnetic pole different from the magnetic pole teeth 38a of the rotor 34 in which the N and S poles are alternately magnetized in the circumferential direction moves to a position coinciding with the rotation direction of the magnetic pole teeth 38a, and the stopper abuts. With respect to the original origin position, which is the state, the width is equal to or less than the width of two pulses in two-phase excitation, and 1-2.
In the phase excitation, a position shift of a width of four pulses or less occurs.

Since the rotation start point of the flow control operation is at the above-mentioned shifted position, even if the number of pulses for obtaining the predetermined opening is applied to the coil, the opening differs by the above-mentioned difference. Therefore, there arises a problem that proper flow control cannot be performed.

This problem is not a serious problem for a multi-rotation type needle-type motorized flow control valve having a total number of pulses of about 500, which is a precedent of various types. In the conventional electric flow control valve shown in FIG. 14 which controls the flow rate by the degree, there is a serious problem that the accuracy of the flow control cannot be ensured.

[0017]

SUMMARY OF THE INVENTION The present invention is directed to an upstream throttle valve portion and a downstream throttle valve portion capable of obtaining different flow characteristics comprising a valve seat and a valve body, respectively, at an upper portion and a lower portion of a cylindrical case. An upper valve body and a lower valve body that can rotate integrally with the rotor within a predetermined range are provided at the upper and lower parts of the rotor, and the one valve body is a refrigerant valve. When the pressure comes into contact with the valve seat of the throttle valve portion, the throttle valve portion on the upstream side of the refrigerant is fully opened regardless of the position of the driving means by providing the other valve body so as to be separated from the valve seat. In the electric flow control valve in which only the throttle valve portion functions as a throttle valve and two throttle valve mechanisms are automatically used depending on the flow direction of the refrigerant, the magnetic pole teeth of the fixed coil, the upper valve seat and Lower valve seat and stopper A fixed stop portion is formed by assembling at a predetermined position, and the N-pole / S-pole magnetization patterns of the integrally rotating rotor, the upper valve body and the lower valve body are The moving-side restricting portion is formed by assembling them at predetermined positions, and when the fixed-side restricting portion and the moving-side restricting portion abut mechanically, the excitation pattern of the stepping motor is reduced. It is an object of the present invention to provide an electric flow control valve with improved accuracy of flow control by using an excitation pattern used as an origin.

That is, in the electric flow control valve according to the first aspect, the upper end portion and the lower end portion of the cylindrical case 31 made of a non-magnetic material have:
An upper valve seat 32 and a lower valve seat 33 provided with valve ports 32b and 33b at positions eccentric from the center, respectively, and a cylindrical rotor 3 disposed in the case 31.
An upper valve body 35 and a lower valve body 36 are provided on the upper and lower portions of the upper valve body 35 and the lower valve body 36 which are rotatable integrally with the end of the rotor.
The upper valve body 35 and the upper valve seat 32 constitute an upstream throttle valve portion 41, and the lower valve body 36 and the lower valve seat 33 constitute a downstream throttle valve portion 42.
The rotor 3 is driven by a driving means of a stepping motor.
4. A heat pump in which the upper valve body 35 and the lower valve body 36 are reversibly operated integrally with each other, and the opening degree of either of the two throttle valve portions is controlled by the rotation of the valve body less than one rotation. In a motorized flow control valve that controls the capacity of the refrigeration cycle by adjusting the amount of refrigerant passing through the refrigeration cycle, the origin of rotation of the rotor 34, the upper valve body 35, and the lower valve body 36 that rotate integrally is determined. At this time, the magnetic pole teeth 38a of the fixed coil 38, the upper valve seat 32 and the lower valve seat 33, and the stopper 4
0 constitutes a fixed-side stop portion by assembling them so as to be at predetermined positions, and the N-pole / S-pole magnetization patterns of the rotor 34, which rotates integrally, and the upper valve body 35 and The lower valve element 36 constitutes a moving-side restricting portion by assembling at a predetermined position, and the valve element rotates in a closing direction or an opening direction in less than one rotation, and is fixed to the fixed-side restricting portion. When the stop portion on the moving side is mechanically stopped by contact, the excitation pattern of the stepping motor is the excitation pattern used as the origin.

Further, the electric flow control valve according to claim 2 is
When positioning the fixed coil 38 and the upper valve seat 32 or the lower valve seat 33, the coil bracket 47 for fitting and fixing the fixed coil 38 to the upper valve seat 32 or the lower valve seat 33 is a fixed coil 38. The coil bracket 47 has a bracket projection 4 corresponding to a predetermined position of the magnetic pole teeth 38a of the fixed coil 38.
7a is provided on the upper valve seat 32 or the lower valve seat 33. One or a plurality of valve seat recesses 3 are provided corresponding to the bracket projections 47a so as to satisfy predetermined requirements.
2d is provided, It is something of Claim 1 characterized by the above-mentioned.

[0020]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below in detail with reference to the drawings. FIG. 1 is a longitudinal sectional view of an electric flow control valve of the present invention. 2A and 2B are perspective views of the upper valve seat according to the present invention, in which FIG. 2A shows a state diagram viewed from the lower surface, and FIG. 2B shows a state diagram viewed from the upper surface. 3A and 3B are perspective views of the lower valve seat according to the present invention, in which FIG. 3A is a state diagram as viewed from above, and FIG. 3B is a state diagram as viewed from below. FIG.
FIG. 5 is an exploded perspective view showing an assembled state of the fixed coil, the upper and lower valve seats, the upper and lower valve bodies, and the rotor of the present invention.

The motorized flow control valve of the present invention comprises upper and lower valve seats 32 and 33 and upper and lower valve bodies 35 and 36 at the upper and lower portions of a cylindrical case 31, respectively, similarly to the conventional product shown in FIG. An upstream throttle valve portion 41 and a downstream throttle valve portion 42 capable of obtaining different flow rate characteristics are formed. The upper and lower portions of the rotor 34 are connected to the rotor 34 within a predetermined range. Upper valve body 35 that can rotate integrally
And a lower valve element 36. When one of the valve bodies (for example, the lower valve body 36) comes into contact with the valve seat of the throttle valve unit due to the pressure of the refrigerant, the other valve body (the upper valve body 35)
The throttle valve on the upstream side of the refrigerant is fully opened regardless of the position of the driving means, and only the throttle valve on the downstream side functions as a throttle valve. Thus, two throttle valve mechanisms are selectively used.

That is, in the electric flow control valve of the present invention, the components of the flow control valve and the operating principle of the valve element are the same as those of the conventional product, and therefore, detailed description thereof will be omitted.

The electric flow control valve of the present invention is shown in FIGS.
As shown in FIG.
In determining the origin of rotation of the fifth and lower valve bodies 36, the magnetic pole teeth 38 a of the fixed coil 38, the upper valve seat 32, the lower valve seat 33, and the stopper 40 are set so that they are at predetermined positions. By attaching it, a fixed-side stopping portion is configured. That is, the fixed coil 38 is integrally provided with a coil bracket 47, and the upper end and the lower end of the coil bracket 47 are fitted to the upper valve seat 32 and the lower valve seat 33, thereby forming the cylindrical case 31. Around the fixed coil (38).

The coil bracket 47 is provided with a bracket projection 47a corresponding to a predetermined position of the magnetic pole teeth 38a of the fixed coil 38. On the other hand, on the upper valve seat 32, the bracket projection 47a is provided. One or a plurality of valve seat concave portions 32d are provided corresponding to the portion 47a so as to satisfy one or a predetermined requirement. The valve seat recess 3
The predetermined requirement when a plurality of 2d are provided is a repetition pitch angle of the magnetic pole teeth 38a provided at a plurality of positions on the fixed coil 38 at equal intervals. Is a position shifted in the rotation direction.
The bracket convex portion 47 is provided in the valve seat concave portion 32d.
a, the stopper 40 provided on the upper valve seat 32 in the illustrated example is positioned at a predetermined position with respect to the magnetic pole teeth 38 a of the fixed coil 38 so as to restrict the fixed side. Unit.

The rotor 34 has N and S poles alternately magnetized in the circumferential direction.
The magnetization pattern of the S pole, the upper valve body 35 and the lower valve body 36
Are assembled so as to be at predetermined positions with respect to each other. Further, in the illustrated example, a locking piece 36f for contacting the stopper 40 is provided at a predetermined position on the lower valve body 36. In other words, the stopper on the moving side is configured such that the locking piece 36f is at a predetermined position with respect to the magnetization pattern of the N-pole and S-pole of the rotor 34. In this way, by forming the fixed-side blocking portion and the moving-side blocking portion, the valve body rotates in a closing direction or an opening direction in less than one rotation, and the fixed-side blocking portion and the moving-side blocking portion. The excitation pattern of the stepping motor is set to be the excitation pattern used as the origin when the parts are mechanically stopped by contact.

The motor-operated flow control valve of the present invention having the above-described structure uses the excitation pattern of the stepping motor as the origin when the rotation of the rotor is stopped by the contact between the fixed-side stop and the movable-side stop. Initialization operation is performed by giving a pulse signal (number of pulses greater than the number of pulses from fully open to fully closed) from the microcomputer at the start of use as an electric flow control valve because the excitation pattern is set to When the mechanical stop by the stopper is performed, the excitation pattern used as the origin, which is the final excitation pattern of the initialization operation, is used. Matches. Accordingly, unlike the conventional product, the origin position of the rotor does not shift after the rotor hits the stopper and stops.

[0027]

As described above, in the electric flow control valve according to the present invention, the N-pole / S
The movable-side restricting portion is formed by assembling the magnetized pattern of the poles and the upper valve body and the lower valve body at predetermined positions, and the fixed-side restricting portion and the movable-side restricting portion correspond to each other. When mechanically stopped by contact, the excitation pattern of the stepping motor is the excitation pattern used as the origin.Therefore, like the conventional product, the rotor's origin position after the rotor hits the stopper during the initialization operation and stops. Since the displacement does not occur, the accuracy of the flow rate control can be improved.

Further, since the valve body is engaged with the rotor and rotates, and the opening degree of the valve is adjusted by rotating the valve seat surface by less than one rotation, the valve body is extremely simplified. When the stopping portion and the moving-side stopping portion are configured, if the angles and dimensions of the components are set, the components can be easily assembled. In other words, in the conventional needle valve type electric flow control valve that controls the valve body by rotating many times,
The screw propulsion structure required complicated component design and adjustment, but this is not the case with the present invention.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing an embodiment of the present invention.

FIG. 2 is a perspective view of an upper valve seat according to the present invention;
Shows a state diagram viewed from the lower surface, and (b) shows a state diagram viewed from the upper surface.

FIG. 3 is a perspective view of a lower valve seat according to the present invention;
Shows a state diagram viewed from above, and (b) shows a state diagram viewed from below.

FIG. 4 is an exploded perspective view showing an assembled state of a fixed coil, upper and lower valve seats, upper and lower valve bodies, and a rotor of the present invention.

FIG. 5 is a longitudinal sectional view of a conventional electric flow control valve.

[Explanation of symbols]

31 cylindrical case, 32 upper valve seat, 33 lower valve seat, 32a, 33
a Shaft bore, 32b Valve contact surface 32c contact surface, 32d Upper valve seat seat recess 33b Valve port, 33c contact surface, 34
Rotor, 34a, 34b notch, 35 upper valve body, 36 lower valve body, 35a, 36a shaft hole, 35b,
36b communication hole, 35c, 36c protrusion, 35d,
36d groove, 35e, position where the sectional area of the 36e groove is maximum, 36f locking piece, 37 shaft, 38 fixed coil, 38a magnetic pole teeth, 39a, 39b inflow / outflow pipe, 40 stopper, 41 upstream throttle valve part, 42 Throttle valve part on the downstream side, 44 Piston ring, 47 Coil bracket, 47a Bracket convex part.

Claims (2)

[Claims] An upper end and a lower end of a cylindrical case (31) made of a non-magnetic material are respectively provided with valve openings (3) at positions eccentric from the center.
2b, 33b) are provided with an upper valve seat (32) and a lower valve seat (33), and a cylindrical rotor (34) disposed in the case (31) has upper and lower portions thereof. An upper valve body (35) and a lower valve body (36) which are rotatable integrally with the end of the rotor and are integrally rotatable, are provided by the upper valve body (35) and the upper valve seat (32). An upstream throttle valve portion (41); and a lower valve body (36).
And the lower valve seat (33), the throttle valve section (4
2), the upper valve body (35) and the lower valve body (36) are reversibly operated integrally with the rotor (34) by the driving means of the stepping motor, and the number of rotations of the valve body is less than one rotation. An electric flow control valve for controlling the capacity of the refrigeration cycle by adjusting the amount of refrigerant passing through the heat pump refrigeration cycle in which the opening degree of either of the two throttle valve sections is controlled by the movement. When determining the origin of rotation of the rotor (34), the upper valve body (35) and the lower valve body (36), the magnetic pole teeth (38a) of the fixed coil (38) and the upper valve seat (32).
And the lower valve seat (33) and the stopper (40) are assembled so as to be at predetermined positions with each other to form a fixed-side stop portion, and the rotor (3) which rotates integrally.
4) N-pole and S-pole magnetization patterns and the upper valve body (3
5) and the lower valve element (36) are assembled so as to be at a predetermined position to constitute a moving-side restricting portion. The valve element rotates in a closing direction or an opening direction in less than one rotation and is fixed. An electric flow control valve, characterized in that the excitation pattern of the stepping motor is an excitation pattern used as an origin when mechanically stopped by abutment of a stop portion on the side and a stop portion on the moving side. 2. When positioning the fixed coil (38) with the upper valve seat (32) or the lower valve seat (33), the upper valve seat (32) or the lower valve seat (33).
A coil bracket (47) for fitting and fixing the fixed coil (38) to the fixed coil (38) is provided integrally with the fixed coil (38).
The coil bracket (47) is provided with bracket projections (47a) corresponding to predetermined positions of the magnetic pole teeth (38a) of the fixed coil (38), and the upper valve seat (32) or the lower valve seat (33). ) On the bracket projection (47a)
The electric flow control valve according to claim 1, wherein one or a plurality of valve seat recesses (32d) are provided so as to satisfy predetermined requirements.